How do resmed machines adapt pressure to AIH events

I have a similar issue. I am nine days into treatment and the first seven were remarkably consistent with the last two nights being quite different. I have the s8 set to auto with this Fisher and Paykel mask.

First seven nights: AI between .8 and 1.2 each night, HI between 7.0 and 8.2.
Last two nights: AI 2.5 and 3.2 and HI 10.2 and 10.5

I know those numbers aren't huge but it seems like I need to tweak something. Any ideas? Also, I am not sure which mask setting I should choose. My leak numbers are .30 to .45 which look high but i think the leak rate for the maskis .37... though i know the s8 adjusts for what is expected.

Thanks in advance.

ozij wrote:Resmed machines in automatic mode areprogrammed not to respond to apenas that occur above a pressure of 10.

Resmed machine cannot distinguish between a obstructive apnea, and one the may be induced by the pressure. So in order to be on the safe side, Resmed's in automatic mode will ignore any apneas that appear when the pressure is above 10.

If your doctor knows for a fact that you have obstructive events above a pressure of 10, you can't trust a Resmed machine on automatic mode to handle them. You either need to switch to fixed mode on the Resmed, or get a kind of machine that handles the problem of "this might be a non-obstructive apnea" differently.

Respironics and Puritan Bennett have automatic machines with a different approach to apneas at higher pressures.

Moderated chat transcript on talkaboutsleep

ResMed's Simon J.P. Johnson wrote:The A10 algorithm increases pressure in response to Flow Limitation, Snore, and Apnea up to 10cm H2O. Above 10cm H2O, pressure response to Flow Limitation and Snore continues, but there is no response to Apnea. AutoSet Spirit and AutoSet T do not differentiate between obstructive and central apneas. Increasing pressures above 10cm H2O in response to apnea can lead to "runaway" central apneas.

Resmed keeps the same algorithm for the Vantage.
My emphasis.
O.

These results don't surprise me. I fiddled around with apap on my resmed spirit for 9 months looking for a range that was effective. I finally gave up and switched to cpap.

Slinky wrote:Are you looking at your Leak rate during these events?

Hello to all,

I record also my leaks level.
Below are the results completed.

As far as the mask is paramatrized in the machine, yes, I have the right mask set.

I don't have the feeling that the leak value is bad.
I also looked at events / leaks on the time line during the night, and even in dense period of apnea, the leak rate reamains around 15 liters/min (0,25 liters per sec) and does not go above 24 liters/min (0,4 liters/ min)

I need to learn how, and I will include one view of my Rescan.


1) Min 4 - Max 20
-Pressure gets established and stable around 10.9
-Average IA is at 2.4 / Avearage Leak95 = 0,16 liters/sec
-Average total time per night in apnea is 5 min
-Worst night : IA = 4.6 / Leak95 = 0,16 liters/sec
-Best night : IA = 1 / Leak95 = 0,42 liters/sec

2) Min 8 - Max 20
-Pressure gets established and stable around 11.4
-Average IA is at 1.3 / Avearage Leak95 = 0,15 liters/sec
-Average total time per night in apnea is 3 min
-Worst night : IA = 1.9 / Leak95 = 0,28 liters/sec
-Best night : IA = 0.4 / Leak95 = 0,16 liters/sec

3) Min 11.4 - Max 20
-Pressure gets established and stable around 12.7
-Average IA is at 1.5 / Avearage Leak95 = 0,18 liters/sec
-Average total time per night in apnea is 3 min
-Worst night : IA = 3.5 / Leak95 = 0,20 liters/sec
-Best night : IA = 0.5 / Leak95 = 0,32 liters/sec

Thanks for your answers.

Pierre